Potassium sulfate solid electrolytes

Figure 25-14. Part of the head of a SO measuring probe with potassium sulfate solid electrolytes in pellet shape for mounting inside the arrangement shown in Figure 25-9 [65].

Thermodynamic equilibria are also of principal importance, if one wishes to determine carbon dioxide or sulfur dioxide with carbonates or sulfates which show conductance for sodium or potassium ions. It is not the ion migrating through the solid, but the electrochemical equilibrium between molecules in the gas phase, particles in the solid electrolyte and electrons in the electrical conductor that determine the electrode potential utilizable in sensors. 

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